It was fall of 1998 when ASHI began reshaping its membership examination into a psychometrically valid, reliable test (“psychometrics” is the science of test development and management). The first step was to determine exactly what domains, tasks, knowledge and skills are required to be a competent home inspector.
That first step is called “role delineation” or “job analysis.” The National Home Inspector Examination (NHIE) implemented in October 1999 under the management of the Examination Board of Professional Home Inspectors (EBPHI) was and continues to be based on a test blueprint drawn from that first role delineation study.
Like other professions, however, home inspection changes over time. Therefore, EBPHI engaged in its second role delineation study in the winter of 2002-2003, in keeping with standards suggested by the American Educational Research Association. This new study serves as the foundation for the NHIE beginning this fall and for the next few years.
Home inspectors defining home inspection
Opinions about what constitutes the content of the profession vary. To generate consensus, EBPHI invited 17 home inspectors to Chicago last fall. These “subject matter experts” (SMEs) were selected first based on their experience and reputation as expert professionals; then on their representation of a state currently using the NHIE for licensing competence assessment; and last to assure geographic and practice specialty representation.
Under the guidance of a psychometric professional, the SME panel discussed the role of the home inspector. The panel determined that the profession could be divided into four major content areas or performance domains, defined as the major responsibilities, duties, or bodies of content that define the role of the home inspector.
Next, the panel delineated the tasks, i.e. activities performed with the domain that form a comprehensive and detailed description of the domain. The panel members evaluated the performance domains and tasks, rating each on importance and criticality to the home inspector and the frequency with which the activities associated with each are performed.
EBPHI 2003 Role Delineation
Study of the Home Inspection Profession
Domain I, Inspection Methods
- Sensory observation
- Measurement methods
- Additional methods
Domain II, Building Systems
- Exterior systems
- Structural systems
- Roofing systems
- Electrical systems
- Heating and cooling systems
- Insulating and ventilating systems
- Plumbing systems
- Interior systems
- Fireplace and chimney systems
- Distinguishing characteristics
- Elements of the inspection contract
- Third-party stakeholders with financial or technical interests
- Conditions of immediate safety concern
- Inspector financial responsibilities
- Professional conduct.
Checking in with home inspectors
The next step in the role delineation process was to survey home inspection professionals across the country. The questionnaire asked them to evaluate, validate and provide feedback on the panel’s domain and task lists.
For the current role delineation study, the questionnaire was sent to a sample of individuals who had passed the NHIE since its inception in October 1999 and individuals selected at random from other sources to insure appropriate geographic representation. Of the 1,860 home inspectors surveyed, a statistically valid sample of 25 percent returned responses.
Respondents rated the domains, tasks and associated topics in three ways. The “importance” of the domains and tasks asks how essential is the task to job performance of a minimally competent home inspector? “Criticality” asks what level of harm would result from incompetent performance in the task? Last, “frequency” asks how often the inspector performs the task.
“Importance:” The results of the survey indicate home inspectors feel that Domain III, Reporting is the most important domain, followed by Domain II, Building Systems, then Domain IV, Professional Practice. Domain I, Inspection Methods was reported as the least important domain.
“Criticality:” Respondents considered Domain II, Building Systems as the most critical of the four domains, followed by Domain III, Reporting and Domain I, Inspection Methods. Domain IV, Professional Practice was reported as the least critical of the four domains.
“Frequency:” The respondents felt that 31 percent of their time is spent performing duties associated with Domain II, Building Systems, 28 percent is spent in Domain I, Inspection Methods, and 26 percent in Domain III, Reporting. The least amount of time at 15 percent is spent in Domain IV, Professional Practice.
Based on these responses for importance, criticality and frequency, a blueprint for future versions of the NHIE has been implemented for fall of 2003. All questions in EBPHI’s item bank have been reclassified according to these domains and tasks and their related knowledge and skills. The percentage of questions on the exam in each domain or content area reflects the statistically valid ratings provided by the survey.
A basis for curriculum development and review
EBPHI will soon make the 2003 Home Inspector Role Delineation Study available to training providers, community colleges and other institutions or individuals who have an interest in the profession. As the trend to license the profession grows and more states adopt the NHIE for purposes of competency assessment, it makes sense for education and training providers to base their curricula on EBPHI’s role delineation study.
EBPHI contributes to the home inspection profession’s continued growth by engaging in continual development, maintenance and administration activities that meet or exceed the highest standards for “high-stakes” tests to be used in regulating the profession.